fish culture y3
TRANSCRIPT
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COMPETENCY-BASEDLEARNING MATERIAL
THIRD YEAR
REPUBLIC OF THE PHILIPPINES
DEPARTMENT OF EDUCATIONPUBLIC TECHNICAL-VOCATIONAL
HIGH SCHOOLS
Unit of Competency: EVALUATE SITE FOR FISHPONDS
Module No.: 1 Module Title: EVALUATING SITE FOR FISHPONDS
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TABLE OF CONTENTS
MODULE IWhat Is This Module About?............................................................. 2
What Will You Learn? ....................................................................... 2
LESSON 1.Evaluating Site For Fishpond .............................................................. 3
What Is This Lesson About? ............................................................. 3What Will You Learn? ....................................................................... 3What Do You Already Know? ............................................................ 3Let Us Study .................................................................................... 4Let Us Remember ........................................................................... 11How Much Have You Learned? ....................................................... 11Let Us Apply What You Have Learned ............................................. 13
Resources ...................................................................................... 13References ..................................................................................... 13
LESSON 2.Evaluating Suitable Site For Fish Pens And Fish Cages ..................... 14
What Is This Lesson About? ........................................................... 14What Will You Learn? ..................................................................... 14What Do You Already Know? .......................................................... 14Let Us Study .................................................................................. 15Let Us Remember ........................................................................... 18How Much Have You Learned? ....................................................... 18Let Us Apply What You Have Learned ............................................. 20Resources ...................................................................................... 20References ..................................................................................... 20
LESSON 3.Evaluating Site For Tank Construction .............................................. 21
What Is This Lesson About? ........................................................... 21What Will You Learn? ..................................................................... 21What Do You Already Know? .......................................................... 21Let Us Study .................................................................................. 22Let Us Remember ........................................................................... 25How Much Have You Learned? ....................................................... 25Let Us Apply What You Have Learned ............................................. 26Resources ...................................................................................... 26References ..................................................................................... 26Answer Key .................................................................................... 27
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MODULE I
QUALIFICATION TITLE : AQUACULTURE NC II
UNIT OF COMPETENCY : EVALUATE SITE FORFISHPONDS
MODULE TITLE : EVALUATING SITE FORFISHPONDS
NOMINAL DURATION : 120 HRS.
WHAT IS THIS MODULE ABOUT?
This module covers briefly the process involved in evaluating sitefor fishpond. It provides the students with basic information andguidelines in putting up fish pens, cages and tanks. It is hoped that thestudents be equipped with ample skills and knowledge in evaluating apond, fishpen, cages and tank site, constructing the project and itsscientific management operation.
WHAT WILL YOU LEARN?
After completing this module you should be able to:
1. evaluate site for fishpond;2. evaluate suitable site for fish pens and cages; and3. evaluate site for tanks.
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LESSON 1.
EVALUATING SITE FOR FISHPOND
WHAT IS THIS LESSON ABOUT?
The lesson covers briefly on how to evaluate site for fishpond. Thisincludes the factors to be considered in selecting a good fishpond site,the best type of soil ideal for fishpond site, the quality of water forfishpond site and the most ideal elevation based on water source/tide.
WHAT WILL YOU LEARN?
At the end of the lesson, you should be able to:
1. determine the factors to be considered in evaluating the goodfishpond site;
2. analyze and sample soil type using Eckman Dredge;3. determine the water source and volume adequacy using flow rate
meter or volume calibration;4. analyze water quality based on standards; and5. determine engineering matter for good water management.
WHAT DO YOU ALREADY KNOW?
Before you go through the lesson, try to answer this pre-test. Thiswill enable you to find out what you already know and what you stillneed to know about evaluating site for fishpond.
Pre-Test
Multiple Choice: Choose the letter of the correct answer. Answer this in
your test notebook.
1. Which of the following is the foremost factor to be considered inevaluating fishpond site?a. ground elevationb. water supply
c. weather conditiond. floor hazard
2. Clay loam is the best soil for fishpond operation because -a. it has greater water holding capacityb. it is a good soil for dike constructionc. it has rich organic deposits
d. all of the above
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3. Which of the following is a socio-economic factor in selecting anideal fishpond site?a. protection from floodb. wind directionc. soil characteristics
d. availability of cheap labor and construction materials
4. In order to satisfy fish requirement for space and oxygen in therearing pond, maintain a depth of water of about -a. 70-100 cmb. 10-20 cm
c. 20-30 cmd. 30-50 cm
5. When the water temperature goes beyond the temperature toleranceof the fish the effect is -a. good growth of natural fish food
b. poor response to supplemental foodc. fish grows fastd. high dissolved oxygen of the water
6. What is the pH of the water when fish thrive well and grow fast?a. 4-5b. 5-6.5
c. 6.5-9d. 10-11
7. Which of the following is a symptom of ammonia toxicity in fish?a. fish starts jumpingb. eroded operculum
c. presence of blood spots on the skind. presence of bloody gills
8. Which refers to the plant that covers the site?a. treesb. shrubs
c. vegetationd. herbs
9. What type of soil has granular appearance?a. siltb. sand
c. clayd. loam
10. What generates wave action in ponds?a. wind blowing across the surfaceb. water current inside the pondc. stock fishd. natural fish food
LET US STUDY
The success of pond construction depends on many factors like
general site suitable for fish production, availability of labor and inputsand socio-economic considerations. Most importantly, site selection plays
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It is best to take an integrated sample from top to bottom inthe middle of the rivers, streams, lakes, irrigation canals in such away that the sample made composite according to the flow. If onlya grab or cuts sample can be collected is best to take it at themiddle of the river at mid depth.
Types of water containers for water sample
In all cases, the following containers shall be chosen so thatsamples will not be contaminated.
a. chemically resistant glassb. polyethylene bagsc. hard rubber container
How to handle and store samples?
It is necessary to keep the samples cool. Keeping the samplesin the storage at low temperature of 40C is the best way to preservethem to obtain reliable results.
Types of samples
a. Grab or catch sample is a single sample taken at neitherset time nor flow. This type of sample maybe taken at anymoment.
b. Composite sampleis a combination of individual sample ofwater at selected interval.c. Integrated sample mixture of grab samples collected from
different points simultaneously.
3. Water Flow Current. The watercurrent meter is a self containedcurrent measuring sensor design tomeasure the true magnitude anddirection of horizontal currentmotion in any water environment.
4. Water Management. The water shouldbe free from toxic chemicalcontamination and unwantedpredators or wild fishes and must beavailable when needed. Employprecautionary measures when usingwater from rivers. streams, andcommunal irrigation system.
Figure 2. Water Current Meter.
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A Simple bio-assay can be done using the following techniques:
Place two or three fishes in a pail full of water from the source tobe tested for at least one-half day.
Place hapa or scoop net with three or five fishes twenty five tofifty meters upstream of the water source.
The water is safe to use when the fishes remains alive afterhalf a day. Ocular inspection or nasal testing to determine thepresence of toxic substances is generally ineffective.
Maintain water depth from 70 100 cm to satisfy fishrequirement for space and oxygen and to prevent over heating ofwater during hot weather.
Employ some management modifications when water supplyis seasonal. When using rain water or irrigation water with limitedflow, it is necessary to increase the volume of pond water byincreasing depth. If possible, store enough water in the pondduring rainy days.
a. Water Quality. Water quality is one of the important factors inensuring a healthy fish population. Water quality in aquaticenvironment considerably affects the growth and reproductionof fishes. If the water quality is beyond tolerable limits fish
health is adversely effected.
b. Water Temperature. All fishes have upper and lower watertemperature tolerance limits. When the temperature goesbeyond the temperature tolerance limit of the fish, the effectsare:
Abnormal metabolism resulting in poor growth, abnormalactivities or stress.
Poor response to supplemental feeds. Very poor feed conversion ratio.An ordinary thermometer or an equivalent device can be used to
measure water temperature.
Figure 3. Thermometer.
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One of the most common causes of high ammonia level inpond is the heavy application of manure. Organic mattersincrease the ammonia level during decomposition and overgrowth of plankton.
2. Soil characteristicsClay, clay loam and sandy clay soils withdeposits of organic matter of about 16% are best for fishponds. Hard mudof the above types are preferable to the soft and very loose kind. Avoidsandy, rocky or stony soils because these do not retain water in theponds. Clay loam type of soil is favorable because it has greater waterholding capacity and has rich organic deposit. It is beneficial that soilanalysis be conducted to measure physico-chemical characteristic of thepond soil.
Analyzing and sampling soil type
Most of our fishpond is constructed on the tidal lands consisting ofalluvial soils which are adjacent to river or creeks near the coastal shoreand estuarine at our near sea level elevation. If you pick a handful of soiland examine it closely, you will find out that it is madeup of mineralsand organic particles of varying sizes. The mineral particles are silt, clayand sand, while the organic particles are plant and animal matters onvarious stages of decomposition. Soil is assigned with textural classes.Depending on their relative properties as sand, silt clay. Each texturalclass exhibits varying color which is based on their chemical
decomposition, amount of organic matter and the degree ofdecomposition.
General Terms TextureBasic Soil Textural
Class Name
1. Sandy soil CoarseModerately coarse
SandySandy loam
2. Loamy Soils Medium Fine sandy loamVery fine sandy loam
LoamSilty loamSilt
3. Clayey Soils Fine Sandy claySilty clayClayClay loamSandy clay loamSilty clay loam
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Field method for identification of soil texture:
1. Sandsoil that has granular appearance2. Sandy loamessentially granular soil with sufficient silt and clay
to make it coherent
3. loama uniform mixture of sand, silt and clay4. Silty loamit contains a moderate amount of finer grade of sand
and only a small amount of day over half of the particle of the silt5. Siltcontains over 80% of silt with very little fine sand clay6. Clay loamfine texture soil breaks into lamps when it dry7. Clayfine texture soil breaks into very hard lumps when it dry8. Organic soilidentification is based on its higher organic content,
sometimes called Peat soil.
Collecting Soil Samples for Analysis
Using the Eckman dredge
Take soil sample from each pond. If the nursery pond is less than0.5 hectare in size, take only two samples. If the pond is larger than 0.5hectare take more random samples as follows:
Pond sizeNumber ofsamples
0.5 2
0.75 3
1.0 4
1.5 6
2.0 8
The following are the steps in getting soil samples:
1. Determine the required number of samples to be taken per pond.2. Get samples at random by inserting a 5 cm diameter pipe into the
soil to a depth of 10 cm.3. Pull out the pipe and empty its content in a box.4. Mix all the samples taken from every pond.5. Air-dry the mixed soil samples and submit to the testing laboratory
for analysis.6. Submit 10 samples if 10 ponds are to be tested.7. Assign a number for each pond and place this in the corresponding
sample.
3. Topography Choose flat terrains for easier excavation andleveling. If the topography is too undulating, the construction costincrease greatly and excavation work removes the fertile portion of thepond bottom. Avoid sites that are frequently flooded. Topography will also
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provide ease in water management and control of fish predators andcompetitors.
4. Wind direction Wind plays a role in fishpond design. Strongwind generates wave action that destroys the sides of the dike. To
minimize this, position the longer pond dimensions parallel to thedirection of the prevailing wind to lessen the side length of the dikeexposed to wave action.
5. Protection from flood If the fishpond site is prone to floodingconstruct a diversion canal along the perimeter dike to divert runoffwater during heavy downpour, construct a larger and higher perimeterdike to prevent inflow of water.
6. Vegetation Refers to the kinds and types of plants that coversthe proposed fishpond site. This will be the point of the bases ofestimation of construction and development cost. If possible avoid thicklyvegetated areas.
7. Accessibility or nearness to market Fish is a perishablecommodity, hence the farther the site to the market the greater thepossibility that the fish undergo post rigor mortis, which will result tolower price.
8. Socio-Economic ConsiderationMatters considered here are theavailability of cheap labor and construction materials within the locality.
As much as possible the site should also be accessible to sufficientsources of fry or fingerlings for ready stocking. The program of operationwill be hampered if fish seeds are not available when needed. Moreoverfish and order situation in the locality should be considered in putting upfishpond project. Nobody would want to stay in a place where peace andorder condition is unattainable. Financial institution is another factor insocio-economic for sources of capital.
LET US REMEMBER
a.The success of fishpond construction depends on the evaluationof a good fishpond site.
b. Always remember that water supply is the foremost factor toconsider in evaluating fishpond site.
HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how much you
have learned from it by answering the post-test. Answer this in your testnotebook.
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Post Test
Multiple Choice: Choose the letter of the correct answer.
1. Which of the following is the foremost factor to be considered inevaluating fishpond site?
a. ground elevation c. weather conditionb. water supply d. flood hazard
2. Which is the most destructive enemy of fishpond industry?a. ground elevation c. weather conditionb. water supply d. flood hazard
3.The fouling of water that can cause deterioration of gates,screens or metal pipes.
a.poor water quality c. industrial wasteb. agricultural pollutants d. all of the above
4.The most ideal elevation for the fishpond site is -a. 1.4 meter0.0 meter above datum planeb. 8 meters above datum planec. .0.0 meter - .50 meter below datumd. 0./30 meter1 meter below datum plane
5. How many hours is the mean interval between two successivehigh level of waters?
a. 6 hrs and 25 minutes c. 16 hrs and 25 minutesb. 12 hrs and 25 minutes d. 20 hrs and 25 minutes6. What is the best type of soil for fishpond site?
a. sandy soil c. clay loam soilb. loam soil d. silky clay soil
7. Which of the examples below is an agricultural pollutant?a. Pesticides c. piggery and poultry wastesb. Fertilizer d. all of the above
8. Which refers to the plants that cover the site?a. trees c. vegetationb. shrubs d. herbs
9. What type of soil that has granular appearance?a. silt c. clayb. sand d. loam
10. What generates wave action in ponds?a. wind blowing across the surfaceb. water current inside the pondc. stock fishd. natural fish food
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LET US APPLY WHAT YOU HAVE LEARNED
a. Students will identify what mineral particles of soil are in the givensample. (Soil samples on the teachers table).
b. What are the physical, chemical and biological parameters thataffect water quality?
RESOURCES
EquipmenttransitFlow rate meterEckman Dredge
ToolsThermometerwater Parameter KitpH meter
REFERENCES
Lasam, G.D. Region 2 Technoguide for Tilapia Department ofAgricultureRegion
Cagauan, A.G. Tilapia Grow Out Systems and Operation Manual.CLSU, Nueva Ecija.
Fishpond Engineering and Management, BFARUNDP -FAO
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LESSON 2.
EVALUATING SUITABLE SITE FOR FISH PENS
AND FISH CAGES
WHAT IS THIS LESSON ABOUT?
The lesson deals on how to evaluate site for fish pens and fishcages. This includes ways of analyzing water current speed, natural fooddetermination, steps in measuring water transparency and monitoringtide elevation.
WHAT WILL YOU LEARN?
At the end of the lesson, you should be able to:
1. analyze water current speed using water current meter;2. determine natural fish food using plankton sampling;3. measure water transparency using the Secchi Disk; and4. monitor tide elevation to establish type of materials and depth of
facilities.
WHAT DO YOU ALREADY KNOW?
Before you go through this lesson, try to answer this pre-test. Thiswill enable you to find out what you already know and what you stillneed to know about evaluating suitable site for fishpens and fishcages.
Pre-Test
Multiple Choice: Choose the letter with the correct answer. Write this inyour test notebook.
1. It is a structure with materials that allows water to freely flowthrough while retaining confined fishes.
a. fish cage c. fish tanksb. Fishpond d. fish sanctuaries
2.The following are the factors to consider in evaluating ideal site forfish pen except -
a. water supplyb. type of soilc. turbidity locationd. topography or elevation
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3. Which of the following does not belong to the group?a. fish pen c. fish trapb. fish cage d. fish tank
4. It is used to measure the magnitude and the direction of horizontalmotion of the water -
a. Water current meterb. Eckman dredgec. Water samplerd. Secchi disk
5.The animal components of planktons which are passively driftingwith water movement.
a. Phytoplanktonsb. Zooplanktonsc.
flagelletesd. detritus
6. Which of the examples below is configured for water columnprofiling and wave measurements?
a. S4 current meterb. Eckman dredgec. Refractometerd. Astronomical regulator
7. How will you collect phytoplanktons during sampling?a. By towing a seine netb. By towing a plankton netc. By setting the varier netd. By installing collecting nets
8. Water transparency is measured using aa. dissolved oxygen meter c. thermometerb. pH meter d. secchi disc
9. Which of the examples below is NOT a kind of natural food?a. lablab c. planktonb. lumut d. darak
10. It is the alternate rising and falling of the surface of the water.a. climate c. waveb. tide d. weather
LET US STUDY
Let Us Define
Currentthe continuous movement of a fluid.Detritusloose materials that result directly from rock disintegration.
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Natural foodsminute plants or animals grown in pond bottom.Secchi discan instrument used to measure water transparency.Sandsoil that has granular appearance.Tidethe alternate rising and falling of the surface of the ocean.Turbiditythe quality of water being muddy, thick or opaque, water due
to suspended soil sediments causing a darkening or obscuring ofclean water.
Vegetationthe kinds of plants covering a site.Fish penan artificial enclosure constructed within a body of water for
culturing fish and fishery aquatic resources made up of polesclosely arranged in an enclosure of wooden materials, screens ornylons netting to prevent escape of the fish.
Fish cagean enclosure which is either stationary floating made up ofnet or screen sewn or fastened together and installed in the waterwith opening at the surface or covered and held in a place by
wooden bamboo post or various types of anchors and floats.
Fish pens and fish cages cannot be constructed in any place. Itssuccess depends on the evaluation of ideal site, proper planning, layoutdesign, proper construction, and appropriate fish pen and fish cagemanagement.
Analyzing Water Current Speed
The water current meter is used to measure the true magnitudeand direction of horizontal current motion in any fresh or salt water in it
can be deployed up to 6000 meters deep. It can be configured for watercolumn profiling and wave measurement. It is particularly useful in:
1. Wave zones where its excellence vertical cosine response is needed.2. Low current regimes where exceptional stability and resolution are
needed.3. Very high flow regimes where low drag and lack of moving parts
permit practical deployment into concern for fragility.4. For long deployment where memory capacity and programmability
are needed.
The S4 current meter utilizes RS-232 serial interface for datatransmission by hardware cable link of up to 1,000 meters.
Sampling of Natural Food
1. General InformationThe suspended matters in the sea consisting of living
organism called plankton and loose particles commonly referred to asdetritus. The term phytoplankton refers to the plant components and
zooplankton refers to the animal components which are passivelydrifting along with the water movements (Zeischel, 1970).
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2. Ecological ImportancePhytoplanktons are among the major producers in the sea.
Though individually small in size, they contribute an enormousquantity of the worlds supply of organic matter. They serve as the
basic food in the sea for various consumers like zooplankton andfishes.
3. PotentialPhytoplankton may play any or all of the following roles in
larvae culture:
Provide nutrient via accidental or active ingestion by thelarvae.
Detrify the water medium by assimilating neutralizinginhibitory materials.
Improve the nutritional value of secondary food organism likeZooplankton
Secrete into the medium metabolic products which facilitatelarval growth and or development.
4. Sampling
Phytoplanktons maybe collected by towing special nettingmaterials (180 meshes/sq. inch) through the water (plankton net) a
receiving container (usually vial) is attached to one end of the net.This serves as a collector.
Two types of plankton net:
Quantitative Qualitative
Characteristic of Mullergaze Net
Meshes never loose Water can easily pass through
Figure 1. Plankton Net
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Measuring Water Transparency Using the Secchi Disc
1. Slowly lower the Secchi Disk into the water.2. Stop when it disappears from sight.3. Note at which point the line breaks the water surface. Mark this
point A.4. After noting at which point along the line the disk just disappears,
lower it a little and then raise until it appears. Mark this point B.5. Measure the transparency of the water as equal to the distance
from the top of the disk to the point C and count the knots alongthe line. This value is the Secchi disc transparency (in cm).
Points To Remember to Obtain Best Measurements
1. Measure Transparency between 0900 and 1500 hrs. on calm days.Whenever possible, make reading when the sun is not of sight.2. Keep the disk clean, particularly the two white quadrants.
Figure 2. Secchi disc
LET US REMEMBER
Phytoplanktons are among the major producers in the sea. Water transparency and current speed are analyzed accurately to
determine an ideal site for fish pens and cages.
HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how much youhave learned from it by answering the post-test. Answer this in your test
notebook.
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Post-Test
Multiple Choice: Choose the letter with the correct answer. Write this inyour test notebook.
1. It is a structure with materials that allows water to freely flowthrough while retaining confined fishes.
a. fish cageb. Fishpondc. fish tanksd. fish sancturies
2. The following are the factors to consider in evaluating ideal site forfish pen except -
c. water supplyd.
type of soile. turbidity location
f. topography or elevation3. Which of the following does not belong to the group?
a. fish penb. fish cagec. fish trapd. fish tank
4. It is used to measure the magnitude and the direction of horizontalmotion of the water.
a. Water current meterb. Eckman dredgec. Water samplerd. Secchi disc
5.The animal components of planktons which are passively driftingwith water movement.
a. Phytoplanktonsb. Zooplanktonsc. flagelletesd. detritus
6. Which of the examples below is configured for water columnprofiling and wave measurements?
a. S4 current meterb. Eckman dredgec. Refractometerd. Astronomical regulator
7. How will you collect phytoplanktons during sampling?a. By towing a seine netb. By towing a plankton netc. By setting the varier netd. By installing collecting nets
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8. Water transparency is measured using a -a. dissolved oxygen meterb. pH meterc. thermometerd. secchi disc
9. Which of the examples below is NOT a kind of natural food?a. lablabb. lumutc. planktond. darak
10. It is the alternate rising and falling of the surface of the water.a. climateb. tide
c. waved. weather
LET US APPLY WHAT YOU HAVE LEARNED
Measure water transparency using the Secchi disc. Compute the mean interval between two successive heights (high
or low water).
RESOURCES
Equipment
Water Current Meter Water Gauge Microscope
Tools
Plankton Net Secchi Disk Eckman Dredge
Facility
Site (bodies of water)
REFERENCES
Li.S. 1994. Fish Culture in Cages and Pens. Beveridge, M.C.M. 1996. Cage Aquaculture. Second Edition. Escover, E.M. and Claveria. R.L. 1985. Economics of Cage Culture
in Bicol Freshwater Lakes.
I D R C/SEAFDEC. 1979. International Workshop on Pen and CageCulture of Fish.
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5. Which of the following type of a tank that can be used either forbreeding nursing fish?a. breeding tankb. conditioning tank
c. nursery tankd. none of the above
6. What kind of tank is used in stocking breeders?a. breeding tankb. conditioning tank
c. nursery tankd. all of the above
7. A type of tank that can give ease to management.a. breeding tankb. conditioning tank
c. nursery tankd. all of the above
8. What affects the rate of biological and chemical processes in water?
a. water quantityb. water temperature c. water turbidityd. water transparency
9. The following affects water temperature except -a. climateb. weather
c. groundwater influxd. dissolved oxygen
10. Water quantity is determine through -a. flow rate meterb. pH meter
c. Eckman dredged. Parameter kit
LET US STUDY
It is very important that the location of the different tanks to beconstructed be inspected and evaluated in order to come up with a veryproductive tank. The land area, size of the tank, water quality andquantity should be considered in evaluating the site for tankconstruction.
Let Us Define
DO meterused to measure the amount of Oxygen dissolved in a unitvolume of water.
Flow rate meterused to measure linear, non-linear mass or volumetricflow of liquid or gas.
Metabolismthe complex of physical and chemical processes in themaintenance of life.
pHthe measure of the acidity and alkalinity of a solution.Refractometerused to determine the concentration of salt and sugar
in water.
Sleevesan encasement into which a piece of equipment fits.Stratificationthe process of arranging or dividing according to
different levels of class or status.
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WATER ANALYSIS
Water Temperature
Water temperature is important because it affects the rates of
biological and chemical processes. Temperature is measured inCentigrade and Fahrenheit (between the freezing and boiling point ofwater).
The health of aquatic organisms from microbes to fish depends ontemperature. If temperature is outside the optimal range for a prolongedperiod, organisms are stressed and can die. For fish, the reproductivestage (including spawning and embryo development) is the mosttemperature-sensitive period. Macroinvertibrates (for example, insects,crayfish, worms, clams and snails) move about in the stream bed to find
their optimal temperatures.
The temperature of the water also affects the volume of dissolvedoxygen (DO), it can hold (waters ability to contain dissolved oxygendecreases as water temperature rises), the form of ammonia (harmful orharmless to aquatic life), the rate of photosynthesis by aquatic plants,metabolic rates of aquatic organisms, and the sensitivity of organisms topollution.
Water temperature is affected by season, weather and groundwaterinflux.
Figure 1. Thermometer.
pH
pH describes the acidity or alkalinity of water and represents the
balance between hydrogen ions (H+) and hydroxide ions (OH-) in water.
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The value for pH is expressed in a scale ranging from 1 to 14.Solutions with more H+ than OH- ions have a pH value lower than 7 andare said to be acidic. Solutions with pH values higher than 7 have moreOH- than H+ ions and are said to be basic or alkaline. If the pH value is7, the solution is said to be neutral (an equal number of H+ and OH ions)
and is neither acidic nor basic/alkaline.
It is important to note that the pH scale is logarithmic. This meansthat each step on the scale represents a tenfold change in the H+concentration. For example, water with a pH of 5 has ten times thenumber of H+ions than water with pH of 6 and is ten times more acidic.
Figure 2. pH meter.
pH of Water
Water with a pH of less than 4.8 or greater than 9.2 can beharmful to aquatic life. Most freshwater fish prefer water with a pH rangebetween 6.5 and 8.4 (colored band on the graph). The pH is also usefulindicator of the chemical balance in water. A high or low pH willadversely affect the availability of certain chemicals or nutrients in thewater for use by plants.
Determining Water Quantity
Water supply is the most important factor in tank culture of fish.The quantity of water needed is based on the following:
1. source of water supply2. size of the tank3. number of tanks in operation4. stocking density
A flow rate meter is used in order to determine the availability ofwater coming from the water source.
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LET US REMEMBER
Tanks must be durable, easy to clean, easy to sterilize and must benon-corrosive.
Water with a pH of less than 4.8 or greater than 9.2 can beharmful to aquatic life.
HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how much youhave learned from it by answering the post-test. Answer this in your testnotebook.
Post Test
Multiple Choice: Choose the letter with the correct answer. Write this inyour test notebook.
1. Which of the following is the foremost factor to be considered inevaluating fishpond site?a. ground elevationb. water supply
c. weather conditiond. floor hazard
2. Clay loam is the best soil for fishpond operation because -a. it has greater water holding capacity.b. it is a good soil for dike construction.c. it has rich organic deposits.d. all of the above
3. Which of the following is a socio-economic factor in selecting anideal fishpond site?a. protection from floodb. wind direction
c. soil characteristicsd. availability of cheap labor and construction materials
4. In order to satisfy fish requirement for space and oxygen in therearing pond, maintain a depth of water of about -a. 70-100 cmb. 10-20 cm
c. 20-30 cmd. 30-50 cm
5. When the water temperature goes beyond the temperature toleranceof the fish the effect is -a. good growth of natural fish food
b. poor response to supplemental foodc. fish grows fastd. high dissolved oxygen of the water
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ANSWER KEY
Pre-Test Post-Test
1. b 1. b
2. d 2. d3. d 3. d4. a 4. a5. b 5. b6. c 6. c7. d 7. d8. c 8. c9. b 9. b10. a 10. a
Lesson 2.
Pre-Test Post-Test
1. a 1. a2. c 2. c3. d 3. d4. d 4. d5. b 5. b6. a 6. a
7. a 7. a8. a 8. a9. d 9. d10. b 10. b
Lesson 3.
Pre-test Post-test
1. c 1. c2. a 2. a3. d 3. d4. b 4. b5. c 5. c6. a 6. a7. d 7. d8. a 8. a9. d 9. d10. a 10. a
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COMPETENCY-BASEDLEARNING MATERIAL
THIRD YEAR
Unit of Competency: DRAW THE LAY OUT PLAN FOR AQUACULTUREFACILITIES
Module No.: 2 Module Title: DRAWING THE LAY OUT PLAN FORAQUACULTURE FACILITIES
REPUBLIC OF THE PHILIPPINES
DEPARTMENT OF EDUCATIONPUBLIC TECHNICAL-VOCATIONAL
HIGH SCHOOLS
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TABLE OF CONTENTS
MODULE IIWhat Is This Module About?............................................................. 2What Will You Learn? ....................................................................... 2
LESSON 1.Drawing The Layout Plan Of A Fishpond ............................................. 3
What Is This Lesson About? ............................................................. 3What Will You Learn? ....................................................................... 3What Do You Already Know? ............................................................ 3Let Us Study .................................................................................... 4Let Us Remember ........................................................................... 10How Much Have You Learned? ....................................................... 10Let Us Apply What You Have Learned ............................................. 11Resources ...................................................................................... 11
References ..................................................................................... 11
LESSON 2.Designing A Tank For Culturing Fish ................................................ 12
What Is This Lesson About? ........................................................... 12What Will You Learn? ..................................................................... 12What Do You Already Know? .......................................................... 12Let Us Study .................................................................................. 13Let Us Remember ........................................................................... 19How Much Have You Learned? ....................................................... 19Let Us Apply What You Have Learned ............................................. 20Resources ...................................................................................... 20References ..................................................................................... 20
LESSON 3.Drawing The Layout Of Fish Pen And Fish Cages............................... 21
What Is This Lesson About? ........................................................... 21What Will You Learn? ..................................................................... 21What Do You Already Know? .......................................................... 21Let Us Study .................................................................................. 22Let Us Remember ........................................................................... 31How Much Have You Learned? ....................................................... 32Let Us Apply What Have You Learned ............................................. 33Resources ...................................................................................... 33References ..................................................................................... 33Answer Key .................................................................................... 34
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MODULE II
QUALIFICATION TITLE : AQUACULTURE NC II
UNIT OF COMPETENCY : DRAW THE LAY OUT PLANFOR AQUACULTUREFACILITIES
MODULE TITLE : DRAWING THE LAY OUTPLAN FOR AQUACULTUREFACILITIES
NOMINAL DURATION : 130 HOURS
WHAT IS THIS MODULE ABOUT?
This module covers the knowledge, skills and right attituderequired in drawing the lay out plan for a fishpond, designing a tank forculturing fish and drawing the layout plan of a fish pen and fish cage.
WHAT WILL YOU LEARN?
Upon completion of this module, you should be able to:
1. draw the layout plan of a fishpond;2. design a tank for culturing fish; and3. draw the layout plan of a fish pen and fish cage.
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LESSON 1.
DRAWING THE LAYOUT PLAN OF A FISHPOND
WHAT IS THIS LESSON ABOUT?
This lesson deals on how to draw a layout plan of a fishpond. Itincludes the factors in selecting fishpond site, the components andcommon accessory units of a fishpond, types of fishpond layouts, scaling,specifications of equipment, tools, and facilities, the advantages of theimproved types of layout and the specifications for different pond designs.
WHAT WILL YOU LEARN?
At the end of the lesson the learners should be able to:
1. draw a fishpond layout into scale;2. stipulate specifications in the layout plan;3. specify clearly the proposed facilities, components and accessory;
units of a fishpond in the layout based on survey result;4. appreciate the determined location and number of water pumps
and ground water resource to be used; and5. plan and layout other fishpond facilities.
WHAT DO YOU ALREADY KNOW?
Before you go through this lesson, try to answer this pre-test. Thiswill enable you to find out what you already know and what you stillneed to know about Drawing the Lay out Plan of a Fishpond.
Pre-Test
Choose the letter with the correct answer. Answer this in your testnotebook.
1. Why are fishpond layouts drawn to scale?a. To lessen labor exerted in the construction.b. To show the layout in a smaller space.c. To show all the compartment units of a fishpond project.d. To display the common accessory units of a fishpond.
2. Which of the following fishpond facilities controls the water of the pondsystem?
a. Main gateb. Secondary gate
c. Tertiary gated. All of the above
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3. What type of fishpond layout has one sluice gate and long watersupply canal that supplies water in the different compartments?a. Conventional c. Progressiveb. Radiating d. Specialized
4. What fishpond unit is intended for rearing fingerlings to marketablesize?a. Transition pondb. Nursery pond
c. Rearing pondd. Brood pond
5. Which among the fishpond units is used as water reservoir?a. Head pondb. Catching pond
c. Rearing pondd. Transition pond
6. Which is intended for the confinement of breeders?
a. Breeding pondb. Rearing pond c. Head pondd. Hatching pond
7. What common accessory unit of a fishpond controls the water in thepond system?a. Secondary gateb. Main gate
c. Tertiary gated. Water supply canal
8. In brackish water fishpond, where should fingerlings be acclimatized?a. Transition pondb. Rearing pond
c. Catching pondd. Nursery pond
9. What is the biggest and highest block of earth that surrounds theentire pond system?a. Main dikeb. Secondary gate
c. Tertiary gated. Main gate
LET US STUDY
Let Us Define
Fishpondan artificial body of water surrounded by dikes and withaccessories such as gates, pipes and canals to facilitate watersupply management.
In view of the high cost of fishpond development, the layout ofimproved types of fishponds, and the specifications for different ponddesigns must be simple and functional. The nature of compartments orunits of a fishpond project is dependent upon the nature and quality ofwater supply and the species of fish to be cultivated.
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Fishpond Lay Out
A one hectare lay out of a conventional pond system with thefollowing specifications:
Area = 10,000 m2NP = 1% of the total production areaTP = 9% of the production areaRP = 80% of the production areaCP = At least 2% of the NP
NP = 10,000 x 1%= 10,000 x 0.01= 100 m2
RP = 10,000 x 80%
= 10,000 x 0.80
= 8,000 m2
CP = 100 x 2%= 100 x 0.02= 2 m2
After the proposed fishpond site is thoroughly examined andselected based on the required factors for pond selection, the following
are the different compartment units, and the common accessories of thepond systems which are to be considered in making the layout plan.
Common Compartment Units of a Fishpond
Figure 1. Transition Pond Figure 2. Rearing Pond
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Figure 3. Catching Pond Figure 4. Water Supply Canal
1. Nursery pond (NP)for the rearing of fish fry to fingerlings size. Themost suitable place is where it can be easily supplied with fresh,unpolluted water all the time and at elevation where it can be readilydrained even during ordinary low tide. The size of the NP dependsprimarily on the fingerling requirements of the rearing ponds based onthe maximum yearly targeted production.
2. Transition pond (TP) - for the storage or acclimatization offingerlings. It is located adjacent to the nursery pond in order to havean effective and easy transfer of fry. Its pond bottom is constructed alittle bit lower than that of the nursery pond.
3. Rearing pond (RP)for raising fingerlings up to marketable size. It isthe largest compartment in the pond system.
4. Breeding pondfor confining breeders.5. Hatching pondfor depositing eggs until these are hatched.6. Catching pond (CP) for confining and catching fry, fingerlings and
fish of marketable size. It is constructed at the gate inside the pondwhere it is intended to be used.
7. Head pondfor storing reserve water.8. Feed pondfor producing food such as lab-lab, lumut or plankton. In
fishpond areas where natural foods not grow well and supplementaryfeeding is necessary, one of the RPs or NPs could be utilized as a feedpond. It should be a separate compartment ideally located near thepond where supplementary feeding is intended.
9. Water supply canalfor supplying water to the differentcompartments.
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Common Accessory Units of a Fishpond
1. Main gatecontrols water in the pond system. It could be wooden orconcrete.
2. Secondary gate controls the incoming and outgoing water in thedifferent pond units
3. Tertiary gates or pipescontrols the incoming and outgoing water inthe smaller compartment of the pond system.
4. Main/perimeter dike surrounds the entire pond system to ensureprotection and safety of the stocks. It is composed of the biggest andhighest blocks of earth and is usually provided with strong basalfoundation and puddle trench.
5. Secondary dike subdivides the pond system into severalcompartments with or without basal foundation and puddle trench.
6. Tertiary dike subdivides the pond system into smallercompartments and serves as partition in the nursery pond.
Figure 5. Main gate Figure 6. Secondary gate
Figure 7. Tertiary gate Figure 8. Main/Perimeter Dike
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Figure 9. Secondary Dike Figure 10. Tertiary Dike
Note:In cases where the source of
water supply fails to provide a fullsupport of water to the pondduring the peak of dry season, thewater pump should be availablewhich may be installed at thecenter part of the pond system.
On the other hand, if gravityflow does not permit for total ponddraining, use water pump to drain the remaining water from the pond.
Types of Improved Freshwater Fishponds Layout
1. Conventional consists of onesluice gate and long water supplycanal. This supplies the differentcompartments.
Figure 12.
2. Radiating has one sluice gate;wide and short supply canal; andsecondary gates in the differentcompartments.
Figure 13.3. Progressive consists of one
sluice gate, long supply canal anda secondary gate provided to
different compartments ofprogressively increasing areas.Figure 14.
Figure 11. Pump
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4. Specializedhas one sluice gate;one or two drainage gates. Twosecondary gates compartment;and a large supply and catchingcanal/pond.
Figure 15.
Advantages of the Improved Types of Layout
1. Easy control of pond water.2. Easy eradication of fish pest and predator.3. Easy means of cropping.4. Pond bottom cultivation can be done when desired.5. Artificial feeding can be conducted easily when resorted to after the
natural food of fish has been consumed.
6.High productivity.
Lay-out Specifications for Brackish water Fishpond Systems
A. Conventional Pond System -The NP comprises about 1% ofthe total production area (TPA).The TP comprises about 9% ofthe TPA. The RP comprisesabout 80% of the TPA. The CPintended for a NP and TP must
be at least 2% of thecompartments watered areaand 1 to 1 if it is intended forthe RP.
Figure 16.Conventional pond system
B. Modular Pond System. The NP comprises about 4% of the TPA. The TPcovers only 6% of the TPA. The RP is divided into three ProductionProcess Sates (PPS). The main idea is to transfer the fingerlings to thenext larger module. The ratio of the area of the three stages of PPS is
1:2:4 for upper PPS and 1:3:9 for lower PPS.
Figure 17.Modular Pond System Figure 18. Multiple Stock /Harvest System
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C. Multiple Stock/Harvest system. There will be at least two (2) NPscomprising six percent of the total production area. A fish holdingcanal (FHC), which holds fingerlings when the rearing ponds are beingprepared, covers at least 1% of each RPs area. It is connected to the
RP in such a way that each RP will have a separate FHC. The RPcovers up to 94% of the TPA including FHC. The general practice is tostock at different times, different sizes, and group of fingerlings andharvests the bigger ones selectively with the use of the gill net.
LET US REMEMBER
A properly laid-out fishpond facilitates efficient water management.
HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how muchhave you learned from it by answering the post test. Answer it on yourtest notebook.
Post Test
Choose the letter with the correct answer.
1. Why are fishpond layouts drawn into scale?a. To lessen labor exerted in the construction.b. To show the layout in a smaller space.c. To show all the compartment units of a fishpond project.d. To display the common accessory units of a fishpond.
2. Which of the following fishpond facilities controls the water of the pondsystem?a. Main gateb. Secondary gate
c. Tertiary gated. All of the above
3. What type of fishpond layout has one sluice gate and long watersupply canal which supplies water in the different compartments?a. Conventional c. Progressiveb. Radiating d. Specialize
4. What fishpond unit is intended for rearing fingerlings to marketablesize?a. Transition pondb. Nursery pond
c. Rearing pondd. Brood pond
5. Which among the fishpond units is used as water reservoir?a. Head pondb. Catching pond
c. Rearing pondd. Transition pond
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6. Which is intended for the confinement of breeders?a. Breeding pondb. Rearing pond
c. Head pondd. Hatching pond
7. What common accessory unit of a fishpond controls the water in the
pond system?a. Main gateb. Secondary gate
c. Tertiary gated. Water supply canal
8. In brackish water fishpond, where should fingerlings be acclimatized?a. Transition pondb. Rearing pond
c. Catching pondd. Nursery pond
9. What is the biggest and highest block of earth that surrounds theentire pond system?
a. Main dikeb. Secondary gate c. Tertiary gated. Main gate
LET US APPLY WHAT YOU HAVE LEARNED
Make layouts of different specifications/areas using:a. conventional pond systemb. modular pond systemc. multiple stock/harvest system
Use an appropriate scale. Compute the area of each compartment using ratio you have
learned from the module
RESOURCES
FacilityProposed pond site
ToolT-square
TrianglePencilScaling rulerDrawing table
MaterialsSurvey resultDrawing padCoupon bondTracing paper
REFERENCES
Cagauan A.G., Tilapia Grow Out Systems and OperationCalmorin L. P., Calmorin M. A., Tinaypan A. S., Introduction to
Fishery TechnologyREGION 02, Technoguide for Tilapia
Rosel R.N. Tilapia Grow-out in Freshwater FishpondSarmiento R.S. Module in Fishpond Engineering and ManagementToledo, C.F. Breeding and Hatchery Management
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LESSON 2.
DESIGNING A TANK FOR CULTURING FISH
WHAT IS THIS LESSON ABOUT?
The lesson deals on how to design a tank for culturing fish. Thisincludes the area and depth of a tank, site selection, number and size ofcompartments, the materials to be used and the life support units for thefish in the tank system.
WHAT WILL YOU LEARN?
After the lesson, you should be able to:
1. determine the area and depth of the tank to conform with theavailable site selected;
2. determine the number and size of the tank compartments;3. determine the materials to be used based on the production targets
and capitalization; and4. appreciate the life support units for the fish to be installed in the
tank system.
WHAT DO YOU ALREADY KNOW?
Before you go through this lesson, try to answer this pre-test. Thiswill enable you to find out what you already know and what you stillneed to know about Designing A Tank For Culturing Fish. Answerthis in your test notebook.
Pre-Test
Choose the letter with the correct answer.
1. How to remedy a tank with low dissolve oxygen?a. Start the blowerb. Start the water pumpc. Start the puddle wheeld. Start the electric fan beside the tank
2. It refers to small aquatic organisms raised in tanks which arecommonly used as the first food of young fin fishes.a. Larvae c. Rotifers
b. Phytoplanktons d. Microalgae
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3. What is the term used to indicate a large container of liquid usuallyused in culturing fish?a. reservoir c. basinb. tank d. fishpond
4. Why is it necessary to design the tanks in the hatchery?a. To have a functional tankb. To create a functional arrangement of tanks.c. To have a uniform size and shape of tanksd. To conform with the characteristics of the target specie of fish
5. What is the first phase of a fish production system?a. construction of aquaculture facilitiesb. hatchery
c. nurseryd. grow-out
6. Separating suspended solids from water such as silts, debris andforeign organisms can be done by the use of -a. fine mesh screenb. secchi disc
c. filtration unitsd. intake structure
7. What is the early stage of fish life cycle?a. eggb. fingerling
c. larvae or fryd. post fingerling
8. How many layers of different filter media are set up in the sand filtertank?a. 2 c. 5b. 4 d. 3
9. What is the design in a milkfish broodstock tank?a. Triangular Squareb. Rectangular d. circular
10. Where are newly hatched fish eggs placed?a. Hatchery tankb. Broodstock tank
c. Nursery tankd. Grow-out tank
LET US STUDY
Let Us Define
Blower a mechanism that increases the draft of air to supply thebellows of an organ.
Broodstock an adult fish kept in tanks or cages to produce eggs forrearing in the hatchery.
Designto prepare plans or sketch or model of something to be made.
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Hatcherya place for the production of fish eggs, larvae and/or fry.Reservoira place where large quantity of water is collected and stored
to have a ready supply of water for use in any eventuality.Sand Filtera mechanism or instrument filled with grades of gravel and
sand, used to remove matter from the water before it enters the
hatchery.Tanka large container of liquids usually used in culturing fish.
HATCHERY TANK DESIGN
Figure 1. Rectangular and Circular Tanks.
The hatchery is the first phase of a production system aimed of
producing fish for human consumption. The next phase is nursery tank.The final phase is grow out culture in ponds, pens, tanks or cages wherefishes are grown to marketable sizes.
Hatchery is a place for the production of fish eggs, larvae and /orfish fry. In practical terms, a hatchery is a building that houses tanksand equipment for eggs cultivation and rearing of larvae. It is an artificiallife-support system for fish taken out of its natural habitat.
The hatchery tanks should be designed in such a way that it
provides for ease of operation and it should also be free from workhazards. The design and layout should take into account the need for thehatchery to expand in the future, so space should be left for the futuretank construction, water and air supply, etc.
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Pump
Larval/ Frytank
Sandfilter
Larval/ Frytank
Rotifer tanks
Figure 2. Basic layout for a small- scale hatchery with 2 larval tanks, 1 sandfilter, 3 rotifer tanks in indoor section, a pump house and 3 microalgae tanks atthe outdoor section.
Tank design and description
The essential type of tanks required in a small scale hatcherieswith 1 meter deep are:
1. Sand filter tankset up with layers of different filter media. Water ispumped in at the top of the tanks, flows to the various media and outat the bottom of the tank.
Seawateroutlet
Sand
Gravel
Large stones
Seawaterintake
Figure 3. Concrete sand filter tanksfor a small hatchery approximately
10 m3capacity.
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2. Larval rearing tank about 6 m3capacity. Generally, this is aconcrete rectangular or squaretank and usually 1 meter indepth. They range in size from 6-
10 m3 capacity.
Figure 4. Larval Rearing Tank
3. Live food production tanks.Microalgae production tanks areusually located outside thehatchery building and are notroofed.
Figure 6. Small fiber-glass tank (1 to 2 m3capacity), for rotifer enrichment
Figure 5. Live Food Production Tanks
Designing Tanks For Culturing Fish
There are various ways of designing fish tanks. These may beconcrete, rectangular or square fish tanks, hexagonal or octagonal fishtanks and the circular tanks. Tanks for grow out are typically 4-10 m indiameter, and 1-3 m deep.
Figure 7. Rectangular Tanks Figure 8. Drain Hall
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Figure 9. Outlet hole Figure 10. Drainage canal
The concrete rectangular tank drain hole fitted with 3 inches PVCpipe is situated at the rear end of the tank (figure 7). The tank floor
should have a slight slope towards the drain hole which is 5 degrees to15 degrees for easy draining, cleaning and for maintaining purposes.
The outlet hole (figure 9) is used for draining water from the tankand the drainage canal (figure 10) is where the water drained from thetank passes out from the tank site.
Figure 11. The circular and hexagonal fish tanks
Figure 12. The cross section of a circular or hexagonal fishpond
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The outlet should be in the middle of the tank. The tank bottomshould have a slight slope towards the center where the outlet isconstructed.
Program of Works
Project: Proposed Rectangular Concrete Tank, 8m x 2m x 1mProject Cost: P 20,000
SCOPE OF WORK Percentage Estimated Cost
I. Excavation 15 % 3,000.00
II. Carpentry Works 10 % 2,000.00
III. Masonry Works 60 % 12,000.00
IV. Plumbing 10 % 2,000.00
V. Electrical Works 5 % 1,000.00
TOTAL 20,000.00
Summary:I. Cost of Materials.. P 12,000.00II. Labor P 20,000.00
Life Support Units
A. Sea water supply systems
intake structure used to draw water from the sea usingelectric motor with 746 watts and 1 hp
filtration unit used to separate suspended solids from thewater, e.g. fine silts, debris and foreign organisms
water pump made of cast iron, stainless steels, fiber glass orplastic is to be used, for this is no subject to corrosion. It mustalso be a self-priming
water pump reservoirprovides a ready source of water for usein any eventuality for reservoirs constructed out of a concretemix
B. Fresh water supply system
A hatchery of either saline or fresh water fin fishes and shellfishes shall also require a standby water pump and accessories to usein drawing water from a well or other sources in case natural watersupply is a problem
C. Air supply systemBlower is always necessary to supply high volume of air at low
pressure in the hatchery. At least one blower with 1-2 hp capacity isneeded although 2 units are better. These will be used in 24-hr cycle,1 will relieve the other after 12 hours of operation.
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Figure 13. Water pump Figure 14. Blower Figure 15. Tank withaerators
LET US REMEMBER
The tank design provides ease and minimizes stress to the fishthrough handling.
HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how much youhave learned from it by answering the post-test. Answer this on yournotebook.
Post Test
Choose the letter with the correct answer.
1. How to remedy a tank with low dissolve oxygen?a. Start the blowerb. Start the water pumpc. Start the puddle wheeld. Start the electric fan beside the tank
2. ____________ are small aquatic organisms raised in tanks which arecommonly used as the first food of young fin fishes.a. Larvae c. Rotifersb. Phytoplanktons d. Microalgae
3. What is the term used to indicate a large container of liquid usuallyused in culturing fish?a. reservoir c. basinb. tank d. fishpond
4. Why is it necessary to design the tanks in the hatchery?a. To have a functional tankb. To create a functional arrangement of tanksc. To have a uniform size and shape of tanksd. To conform with the characteristics of the target specie of fishes
5. What is the first phase of a fish production system?a. construction of aquaculture facilities c. nurseryb. hatchery d. grow-out
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6. Separating suspended solids from water such as silts, debris andforeign organisms can be done by the use of -a. fine mesh screenb. Secchi disc
c. filtration unitsd. intake structure
7. What is the early stage of fish life cycle?a. eggb. fingerling
c. larvae or fryd. post fingerling
8. How many layers of different filter media are set up in the sand filtertank?
a. 2 b. 4 c. 5 d. 3
9. What is the design in a milkfish broodstock tank?a. Triangular b. Rectangular c. Square d. circular
10. Where are newly hatched fish eggs placed?a. Hatchery tankb. Broodstock tank
c. Nursery tankd. Growout tank
LET US APPLY WHAT YOU HAVE LEARNED
Design a milkfish broodstock tank. The size, shape and depth ofthe tank must be stipulated in the design to conform to thecharacteristics of the fish.
RESOURCES
FacilityProposed tank site
MaterialsSurvey resultDrawing tableRuler/ t-square
scaling rulertrianglepencildrawing pad
REFERENCES
Castanos M.T. SEAFDEC Asian [email protected] R.S. Article from SEAFDEC Asian AquacultureSim S.Y., Rimmer M.A., Toledo J.D., Sugama, S.,Rumengan I.,
Williams, K.C.. Philips, M.J. 2005. A Guide to Small-ScaleMarine
Finfish Hatchery TechnologyToledo C.F. Breeding and Hatchery Management
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LESSON 3.
DRAWING THE LAYOUT OF FISH PEN AND FISH CAGES
WHAT IS THIS LESSON ABOUT?
The lesson deals on how to draw a layout plan of fish pens and fishcages. This includes the area, depth, size and shape of the facilities,materials for the frame, mooring, types of net, mesh size and theestimated cost of materials to be used.
WHAT WILL YOU LEARN?
After the lesson, you should be able to:
1. determine the area and depth of facilities conforming to theavailable site selected;
2. appreciate the identified materials for frame and types of net to beused based on the site selected and species to be cultured;
3. estimate the cost of materials identified for the area;4. determine the mesh size of the net based on the size of fingerlings
and species of the fish; and5. identify other farm facilities needed for the layout of fish pens and
fish cages.
WHAT DO YOU ALREADY KNOW?
Before you go through the lesson, try to answer this pre-test. Thiswill enable you to find out what you already know and what still need toknow about Drawing the Layout of Fishpen and Fishcages. Answerthis in your notebook.
Pre-Test
Choose the letter with the correct answer.
1. What factor usually determines the depth of fish cages?a. capability of the ownerb. natural productivity of the waterc. the mooring systemd. the species of fish to be cultivated
2. What is the smallest unit of a net?a. mesh c. knotsb. mesh size d. twine
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3. In order to make the fish cage floats on the water, the cage must beequipped with -
a. mooring systemb. netting systemc. frameworkd. floatation system
4. As a general rule, what is the length of the mooring lines?a. two times of the depth of waterb. three time of the length of the cagec. three times of the depth of the waterd. two meters allowance during high tide
5. Which of the following keeps the whole cage in a certain locationand prevents it from drifting along the water current?
a.mooring c. frameworkb. floater d. barrier
6. What part of the cage serves as the walkways for working, feedingand monitoring?
a. frames c. mooringb. floaters d. nets
7. What type of net cage fabrication refers to a inch mesh?a. CC-net c. B-netb. DD-net d. knotless NET
8. What aquaculture facility is usually supported by a fixed rigidframework of bamboo poles, palm tree poles and wood poles?
a. floating fish cage c. fixed fish cageb. fish pen d. happa
9. Generally, they are the most suitable in relatively large bodies ofwater and along protected coastal areas where level ranges onlyfrom 2.0 meters to a maximum of 7.0 meters.
a. floating fish cage c. fixed fish cageb. fish pen d. fishpond
10.In general, which aquaculture facility has the biggest area?a. fixed fish cage c. fish tankb. floating fish cage d. fish pen
LET US STUDY
Let Us Define
Fish cage is a structure fully enclosed by nets on all sides and bottomsupported either by a fix rigid frame or by floats which rise and fallwith the water or tide level.
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Fish pen is an area enclosed by nets on all sides and utilizes the lakebed and other bodies of water as the bottom enclosure.
Anchor is a heavy object usually a shaped iron weight with flukes,lowered by a cable or chain to the bottom of a body of water to keepa vessel from drifting.
Mesh is the smallest unit of a net.Framework is a structure, usually rigid, serving to hold the parts of
something together or to support something constructed.Knotis a lump made by intertwining the thread in which one free end
is passed through a loop and drawn tightly.Mesh sizeis the distance between the centers of the opposite knots in
the same mesh when it is fully extended at the right angles to thecontinuing direction of the twines.
Net is a fabric of thread, cord, rope or twine woven or knotted to forman open pattern or mesh used to catch fish.
Fouling is the process by which an object or materials get extremelydirty or impure, disgustingly filthy, so offensive to the senses,Mooringare the lines, cables, etc. by which water craft or any floating
objects or moored or held in place.
Before making the layout of the cage/pen, the size, depth andshape must be considered which is dependent mainly on the ability of theowner as far as operation and maintenance is concerned. The biology andbehavior of the target species and the characteristics of the project siteshould be considered as well. The design must be simple but durable,easy to construct and economical.
Determining the Size, Depth and Shapes of Facilities and TargetSpecies of Fishes
In Laguna Lake, Philippines, size of pens range from less than onehectare to more than 100 hectares. The shape of the enclosure isinfluenced by the characteristics of the cultured fish. For milkfish andtilapia, square and rectangular pens are commonly used. Circularenclosures are recommended for big head carp. Generally, the mosteconomical shape of the pen is one that has the least perimeter. Circular
shape require the least materials per unit area but relatively hard toconstruct.
Generally, fish pens are most suitable in relatively large bodies ofwater and along coastal protected areas where the water level ranges onlyfrom 2.0 meters to a maximum of 7.0 meters.
On the other hand, the depth of the cage is usually determined bythe natural productivity of the water. Since natural food production isrelatively higher in the surface, sunlight penetration is usually employedas the basis for depth.
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TYPES OF CAGE
A. Fixed typeThe fixed types of fish cages are suitable for relatively shallow
areas. They are usually installed near shore or in shallow lakes likeLaguna de Bay where water depth is less than five meters. In fixedtype cages, synthetic net cages are attached to bamboo polesstaked to the bottom for support. Size of cages range from 5m x15m with net mesh sizes of 5-15 mm.
Figure 1. Fixed Fish Cage
B. Floating type
Figure 2. Floating Fish Cages
The floating types of fish cages are suitable for depths exceedingfive meters. Floating net cages are typically suspended from
bamboo raft with or without plastic drums or any other floatingmaterials to float. Cages have a net mesh size of 15 mm and vary insize from 15 x 10m to 20m x 15 m with a depth of 5-6 m.
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GENERAL DESIGNS OF CAGES
Figure 3. Square or rectangular cages
Figure 4. Circular cages
Materials and types of nets
A. Fish Pen
1. Framework/structurea. bamboo- most commonb. wooden polesc. anahaw (palm tree) logsd. creosoted pole- pole treated with creosote (wood
preservatives)e. steel/ G.I. pipe
Figure 5. Bamboo Poles Figure 6. Anahaw
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2. Enclosure and Barrier netsa. polyethylene netsb. polypropylene netsc. nylon netsd. woven bamboo splits
Fig. 7. Polyethylene net Fig. 8. Polypropylene Fig 9. Nylon netnet
3.Tying and Braiding netsa. polyethylene rope and twineb. polypropylene ropec. nylon threadsd. nylon cord (monofilament)e. rubber tire strips
Fig. 10. Polyethylene rope Fig. 11. Polyethylene Fig. 12. Polypropylene ropetwines
Fig. 13. Nylon thread Fig. 14. Nylon cord Fig. 15. Rubber strips
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B. Fish Cage
1. Framework/ structurea. bamboo- most commonb. wooden polesc. anahaw (palm tree) logsd. creosoted polee. steel/ G.I. pipeFigure 16.
Materials thatcan be used for
frame.
2. Enclosure and Barrier netsa. polyethylene netsb. polypropylene netsc. nylon netsd. woven bamboo splits
3. Tying and Braidinga. polyethylene rope and twineb. polypropylene ropec. nylon threadsd. nylon cord (monofilament)e. rubber tire strips
4. Floatsa. bamboob. steel drum/ barrelc. Styrofoamd. plastic containere. aluminum cylinderf. PVC pipesg. Rubber tiresFigure 17.Commonly usedmaterials forfloaters.
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5. Sinkersa. stoneb. concrete slabsc. bamboo and wooden pegs
Figure 18. Materials used for sinkers.
Types of Nets and Mesh Sizes Suitable for Fish Pen and Fish Cage
Generally, the most suitable nets should be flexible or adaptablefor easy handling, resistant to fouling growth, heat, and ultraviolet rays.
The mesh size to be used must be small enough to prevent theescape of fish and entry of predators. For hatchery operations of tilapia,the most common sizes of mesh used are 0.5 mm (happa) for breeding,10 mm for nursery and 20 mm for grow-out. However, as long as theescape of the fish does not permit, large meshes are recommended sincethey provide large passageway for water circulation, slower rate offouling, easier to handle and less expensive per unit area.
Type Of Nets For Cage Fabrication
B- NET (1/4 mesh) DD- NET (3/8 mesh) CC-NET (1/2 mesh)There are many kinds of nets that could be used for fabrication.
The most common are the B-net (1/4 mesh), DD-net (3/8 mesh), andCC-net (1/2). However, the most popular is the B-net because smaller
fingerlings do not need a nursery cage. It is cheaper per unit areabecause it is wider (108 inches) than the other nets, hence, labor cost infabricating cages is much lower, and tearing of one or two mesh do noteasily provide an escape route for bigger fishes.
Floating System (Floating Fish Cage)
The floats to be used in floating cages must have the following:a. High buoyancyb. resistant to foulingc. can withstand forces of the wind and waves
For longer life and less fouling attachment, floats used may becovered with protective materials such as rubberized canvass.
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Mooring System
Mooring lines should be light and strong, flexible, highly resistant tofatigue, impact, abrasion, stretch and twisting. As a general guide, thelength of the mooring lines should be three times the depth of water.
Materials commonly used in the fabrication of synthetic fiber ropesare:
a. nylon (polyamide)b. Dacron (polyester)c. Polypropylened. Polyethylene
Nylon is recommended for the high strength and high shockabsorption requirements.
Anchor (floating Fish Cage)
An ideal anchor must provide enough holding power withreasonable weight size. The type of anchor to use in the mooring systemdepends on the depth of water, nature of bottom, and current. The threetypes of anchors are:
1. Dead weight anchors- they are recommended for mooringinvolving essentially vertical tension. A typical example is aconcrete block.
Figure 19.Dead WeightAnchors
2. Embedment anchors- are designed to dig into the bottom as theyare being pulled by a horizontal force. It is recommended forsandy and muddy bottom.
Figure 20.EmbedmentAnchors
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3. Special anchors- are combinations of deadweight and embedmentanchors. They are designed to resist vertical and horizontalcomponents of tension.
Floating Fish Cage
Figure 21. Floating Fish Cage
Exercise 1Draw a 10 x 5 x 5 meter floating fish cage. Label the
materials used. Use appropriate scale.
Figure 22. Fixed Fish Cage
Exercise 2Make a layout of a 5 x 5 x 3 meter fixed (stationary)
fish cage. Label the different materials used.
FIXED FISH
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Figure 23. Small Boat and Bamboo raft.
The small boat and bamboo raft are farm facilities commonly used inselecting the ideal site and laying out of fish cage and fish pen. Theyare the most economical water craft to use in the farm site.
Materials Required for the Construction of Hectare Fishpen
LET US REMEMBER
The layout of a fish pen and fish cages must be durable,economical and functional.
Fish pens and cages must be kept in their stations with theuse of posts and mooring system respectively.
Fish pens and cages both use nets to contain the fishes wewant to grow.
MATERIALS/DESCRIPTION QUANTITY1. Framework
Bamboo poles, 4.5 dia.. 10-12m long with 2 tip250 pcs
2. Pen enclosurePolyethylene net cc-net 17 knots, knotless 192mesh depth.
520 m
3. Barriers net enclosurePolyethylene net, 7 knots, knotted, 27 mesh depth
100 m
4. Rope for tying and nettingPolyethylene rope, 5mm dia., black 200 m/roll
12 rolls
5. Twine for net/barrier assemblyPolyethylene twine, 1mm dia., black 200 m/roll
11 rolls
6. Sinker stone 1 thick 5 dia. 100 pcs.
7. Bamboo stick 1 m long 100 pcs.
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HOW MUCH HAVE YOU LEARNED?
Now that you have finished the lesson, lets find out how much youhave learned from it by answering the post-test. Answer this on yournotebook.
Post Test
Choose the letter with the correct answer.
1. What factor usually determines the depth of fish cages?a. capability of the ownerb. natural productivity of the waterc. the mooring systemd. the species of fish to be cultivated
2. What is the smallest unit of a net?a. mesh c. knotsb. mesh size d. twine
3. In order to make the fish cage floats on the water, the cage must beequipped with -
a. mooring systemb. netting systemc. frameworkd. floatation system
4. As a general rule, what is the length of the mooring lines?a. two times of the depth of waterb. three time of the length of the cagec. three times of the depth of the waterd. two meters allowance during high tide
5. Which of the following keeps the whole cage in a certain locationand prevents it from drifting along the water current?
a. mooring c. frameworkb. floater d. barrier
6. What part of the cage serves as the walkways for working, feedingand monitoring?
a. frames c. mooringb. floaters d. nets
7. What type of net cage fabrication refers to a inch mesh?a. CC-net c. B-netb. DD-net d. knotless NET
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8. What aquaculture facility is usually supported by a fixed rigidframework of bamboo poles, palm tree poles and wood poles?
a. floating fish cage c. fixed fish cageb. fish pen d. happa
9. Generally, they are the most suitable in relatively large bodies ofwater and along protected coastal areas where level ranges onlyfrom 2.0 meters to a maximum of 7.0 meters.
a. floating fish cage c. fixed fish cageb. fish pen d. fishpond
10.In general, which aquaculture facility has the biggest area?a. fixed fish cage c. fish tankb. floating fish cage d. fish pen
LET US APPLY WHAT HAVE YOU LEARNED
Draw the layout of a 5 m. x 5 m. x 3 m. floating fish cage. Include inyour drawing the anchors used which are attached to the mooring linesand label each part.
RESOURCES
Drawing table Strings
Ruler/T- square NetsProposed pen/cage site NailsDrawing pad Brass pegPencil Floats and sinkersWooden post Coal tars
REFERENCES
Cagauan, A. G. Tilapia Grow Out Systems and Operation Manual,CLSU Nueva Ecija
Lasam, G. D. Technoguide for Tilapia. Department of Agriculture-Region 2
Vivar, A. V. SEAFDEC Aquaculture Department
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ANSWER KEY
Lesson 1
Pre-test Post test
1. b 6. a 1. b 6. a2. a 7. b 2. a 7. b3. a 8. a 3. a 8. a4. c 9. a 4. c 9. a5. a 5. a
Lesson 2
Pre-test Post-test
1. a. 6. c 1. a. 6. c2. c 7. c 2. c 7. c3. a 8. d 3. a 8. d4. d 9. d 4. d 9. d5. b 10. c 5. b 10. c
Lesson 3
Pre-test Post test
1. b 6. a 1. b 6. a2. a 7. c 2. a 7. c3. d 8. b 3. d 8. b4. c 9. b 4. c 9. b5. a 10. d 5. a 10. d
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COMPETENCY-BASEDLEARNING MATERIAL
THIRD YEAR
Unit of Competency: CONSTRUCT AQUACULTURE FACILITIES
Module No.: 3 Module Title: CONSTRUCTING AQUACULTUREFACILITIES
REPUBLIC OF THE PHILIPPINES
DEPARTMENT OF EDUCATIONPUBLIC TECHNICAL-VOCATIONAL
HIGH SCHOOLS
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TABLE OF CONTENTS
MODULE IIIWhat Is This Module About?............................................................. 3What Will You Learn? ....................................................................... 3
LESSON 1.Constructing Fishpond ........................................................................ 4
What Is This Lesson About? ............................................................. 4What Will You Learn? ....................................................................... 4What Do You Already Know? ............................................................ 4Let Us Study .................................................................................... 5Let Us Remember .......................................................................... 16How Much Have You Learned? ....................................................... 16Let Us Apply What We Have Learned .............................................. 17Resources ...................................................................................... 17
References ..................................................................................... 17
LESSON 2.Constructing Fish Tanks ................................................................... 18
What Is The Lesson About? ............................................................ 18What Will You Learn? ..................................................................... 18What Do You Already Know? .......................................................... 18Let Us Study .................................................................................. 19Let Us Remember ........................................................................... 29How Much Have You Learned? ....................................................... 29Let Us Apply What You Have Learned ............................................. 31Resources ...................................................................................... 31References ..................................................................................... 31
LESSON 3.Constructing Fish Cage And Fish Pen ................................................ 32
What Is The Lesson About? ............................................................ 32What Will You Learn? ..................................................................... 32What Do You Already Know? .......................................................... 32Let Us Study .................................................................................. 34Let Us Remember ........................................................................... 44How Much Have You Learned? ....................................................... 44Let Us Apply What You Have Learned ............................................. 46Resources ...................................................................................... 46References ..................................................................................... 46Answer Key .................................................................................... 47
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MODULE III
QUALIFICATION TITLE : AQUACULTURE NC II
UNIT OF COMPETENCY : CONSTRUCT AQUACULTUREFACILITIES
MODULE TITLE : CONSTRUCTINGAQUACULTURE FACILITIES
NOMINAL DURATION : 160 HOURS
WHAT IS THIS MODULE ABOUT?
This module covers briefly the process in constructing fishpond. Itprovides the students basic information and guidelines in constructingfishpond, fish tanks, fish pens and fish cages.
WHAT WILL YOU LEARN?
After completing this module, you should be able to:
1. construct fish pond;2. construct fish tanks; and3. construct fish pen and fish cages.
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5. Structure dug at the center of the dike foundation to strengthen thedike.a. slope c. top widthb. mitsa d. bed width
6. The main gate is constructed at the -a. corner of the dikeb. shorter side of the pondc. lowest part of the fishpond at the straight stretch of the streamd. center part of the dike
7. A concrete class A mixture has a ratio of (cement: sand: gravel) -a. 4:2:1b. 4:1:2
c. 2:1:4d. 1:2:4
8. It is the complete removal of tree stumps and root systemembedded in the soil.a. falling b. underbrushing c. uprooting d. withering
9. What part of the gate that serves as the foundation of thestructure?a. apron b. braces c. bridge d. floor
10. The ratio of horizontal length to the vertical height is called -a. freeboard c. side slope
b. top width d. base
LET US STUDY
The construction of ponds should be carried out systematically,economically and continuously within the stipulated time frame. Time isinfluenced by weather conditions and available labor, materials andequipment. In order to attain the most economical implementation of theproject, full utilization shall be made of all the materials, labor andequipment.
Let Us Define
Designa preliminary sketch or planGatea structure that is used to control water flowLayouta diagram showing how something is constructedPerimeter dike a dike that encloses the entire facility and render
overall protection to the cultured stockPlana drawing or diagram drawn on a planeSitea place where construction work is taking place
Seepagethe act or process of seeping
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Development of New Area
When all the requirements needed are at hand, fishpondconstruction starts as planned. The system of farm construction will bebased on the prepared program and schedule of development. In cases
where capital is limited, partial construction can be practiced. That is, bydeveloping a portion of an area and the remaining parts or area shall beconstructed or developed using the income from the constructedfishpond.
Clearing the Area
Underbrushingcutting grasses, bushes, vines, shrubs and smalltrees. It is done by manual labor and the work should commencewhen the foundation of the main dike and the main gate have been
established. Witheringto kill back the trees by filling up the pond with water.
Falling cutting down big trees left after underbrushing. Thefalling operation should commence when the trees bark begins topeel, but before the leaves and branches fall.
Burning usually carried out when the dead trees have becomedry.
Uprooting of stumps and root systemthe complete removal oftree stumps and root system embedded in the soil.
Water Control Structures
A. Main gate. The main gate links the pond system to the source ofwater. It regulates the exchange of water between the pond systemand the tidal stream or sea. It should be concrete for effective controland to last longer. The main gate is usually situated at the centralside of the proposed fishpond facing the source of water. The followingprovides some information needed in the design of the main gate.
1. The floor elevation of the main gate should be lower than the lowestpond bottom, elevation desired inside the pond system. It should
also be lower than extreme low tides. Preferred elevation is -0.30mor 0.30m lower than the zero datum.2. The height of the main gate depends upon the top elevation of the
main dike which is also dependent upon the tidal fluctuation, floodand other factors in the area.
3. The opening of the main gate depends upon how large the area tobe flooded. Experience tells us that a 1.0 m opening main concretegate will flood a 10-15 hectare p